16... d7d5 [%c_effect d5;square;d5;type;Inaccuracy;persistent;true] This move allows White to close the center, reducing the potential of the dangerous light-squared bishop. 17. e4e5  17... e8g8  18. h4h5  18... f6f5 [%c_effect f5;square;f5;type;GreatFind;persistent;true]